#include <stdio.h>

double fact(int number);

int main()
{
    int m,n;
    scanf("%d %d",&m, &n);
    if (m == 0) {
        printf("result = 1\n");
    } else {
    long long result_n = fact(n);
    long long result_m = fact(m);
    long long result_nm = fact(n-m);

    long long result = result_n / (result_m * result_nm);
    printf("result = %lld\n", result);
    }

    return 0;
}

double fact(int number) 
{
    int i = 0;
    long long ret = 1;
    for(i = 1; i <= number; i ++) {
        ret *= i;
    }
    return ret;
}
